EMDR therapy helps victims of abuse reprocess their trauma by moving their eyes around or tapping them on the leg. Some say that treatment has changed their lives.

“Think about the first time you felt like that,” the therapist says to her patient, leaning over and tapping her leg. “Tell me about the first time you felt like you didn’t feel protected.”

“I’m 13 years old,” begins Claudia Gonzalez. The 34-year-old from South Bay, California was sexually abused by her father throughout her childhood, and her relationship with her mom suffered as a result. She felt neglected, and they struggled to get along. “I’m sitting in the hallway of my house, and it’s just me sitting, and my mom's with my dad. The hallway is really dark. I’m crouching on the ground.”

Gonzalez’s therapist, Rajani Venkatraman Levis, continues to tap her knee with an index finger. Together, Gonzalez and Levis go through the process of reprocessing Gonzalez’s hallway memory using a little-known psychotherapy technique called eye movement desensitization and reprocessing (EMDR).

They replay the hallway scene multiple times, each time expanding upon a theme or memory that feels overwhelming. As Gonzalez describes the images in her head, Levis taps her leg or waves her finger back and forth in front of Gonzalez's face, pulling her gaze with it. They repeat the process until the memory feels less traumatic.

Towards the end of the session, Levis encourages Gonzalez to talk to her 13-year-old self and comfort her. “This isn’t how things are now,” Gonzalez tells her teenage self. “You’re strong.”

At the end of the therapy session, her mother—they are now much closer—arrives at Levis' San Francisco office to comfort her. “It was like a full circle,” Gonzalez later explains over the phone. "It was only when I started doing EMDR therapy that I could develop a significant relationship with my mother."

EMDR therapy was first developed by American psychologist Dr. Francine Shapiro in the 1980s. As a relatively recent form of psychotherapy often used to treat post-traumatic stress disorder, it is much more physical than regular talking therapies. As part of an eight-phase treatment protocol, practitioners help their patients reprocess trauma by asking them to recount distressing memories as they move their eyes from side to side, or tap their patients on their hands or legs (known clinically as “bilateral stimulation”). It’s an unorthodox approach, but EMDR therapy acolytes are evangelical about its therapeutic potential.

“When something terrible happens, or something that overwhelms the nervous system occurs,” Levis explains, “it gets stuck in time and is stored in the same way that was taken into the nervous system. It is frozen in place in the brain in a way that gets easily triggered and thus over-accessed. And such a memory can continually overwhelm the nervous system, causing it to shut down.”

Claudia Gonzalez. Photo courtesy of subject

Levis favors a digestion metaphor when explaining EMDR therapy to her patients. When you eat a healthy meal, your digestive system processes the food and eliminates the toxic waste, she explains. But when you eat a greasy or over-processed meal, your body can’t digest it easily. You feel uncomfortable, bloated, or uneasy. “In the same way, EMDR therapy gives the brain support to digest an overwhelming and traumatic memory and assimilate the valuable lessons, while disregarding and eliminating the toxic waste material."

The core premise of EMDR therapy is that PTSD is caused by disturbing memories that haven't been adequately processed. As a result, these memories are easily triggered, causing a negative emotional response. According to the American Psychological Association (APA), EMDR therapy aims to tackle these memories by changing the way they are stored in the brain.

When patients receive bilateral sensory input as they focus on the traumatic memory, the brain is thought to re-process the memory, making it less vivid and distressing. At least 20 randomized controlled studies have taken place looking at EMDR therapy's therapeutic potential for PTSD sufferers. One 1997 study found a 90 percent PTSD remission rate in sexual assault victims after three 90-minute sessions, though it had a relatively small sample size of 18 participants.

In a New York Times piece, Shapiro admits that scientists are still trying to explain the exact mechanisms behind its efficacy, writing, "Controversy remains regarding why EMDR works... We await the results of randomized controlled trials to further determine what role eye movements and other bilateral stimulation make to treatment outcome independent of the rest of EMDR procedures."

There is no clinical data on what proportion of EMDR therapy patients have experienced sexual abuse, but Levis estimates that up to 80 percent of her patients have been victims of sexual violence. Many are women in their 20s or 30s who struggle with intimacy in romantic relationships due to old, unprocessed trauma.

Levis is like an engineer toiling in the sewers of a city; her job is to roll up her sleeves and literally unblock neural passageways. “Say a perpetrator was wearing a specific cologne at the time of the assault,” she tells me. “It may be 20 years later, but when you smell it again, your body goes into high alert and you shut down. So what you need to do is help the mind separate the past from the present.”

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Twenty-six-year-old Tessa Fleming, from San Francisco, was raped while on a family vacation in Mexico. A man in a nightclub attacked her after spiking her drink. She was 16 at the time.

“I remember a staircase and the concrete floor of the nightclub’s second floor,” Fleming says. “Then, I left my body and saw him having sex with me from a bird’s eye view.”

After the assault, she experienced anxiety and shame related to her sexuality. “Before EMDR therapy, if I thought about my rape, it felt like knives stabbing me in my heart and stomach,” Fleming says. “The horrible feeling in my stomach would rise up, seemingly out of nowhere, and I would have to pretend I was fine, that nothing happened. I was so afraid of men, I didn’t have sex for five years.”

It can take weeks for Fleming and her therapist, Ben Yokoyama, to reprocess a single traumatic experience using EMDR therapy. “It doesn’t delete all my memories like in Eternal Sunshine Of The Spotless Mind,” she explains. “But it makes it so that I can remember the memory without my whole body re-feeing the trauma.”

As a general rule of thumb, Yokoyama tells me, a simple trauma—a car accident, mugging, or earthquake—can be reprocessed in three to five sessions. Complex trauma, like sexual violence, is much more difficult to treat, especially when it's historic. "For adult survivors of childhood trauma, the process does involve more time as there are many memory networks associated with the trauma," Levis explains.

Patients like Gonzalez believe that one significant advantage of EMDR therapy over talk therapy is that it takes less time. “Talk therapy is useful, but it takes ages to figure something out. EMDR therapy is much faster. It’s been 15 years, and only now am I able to have a meaningful relationship with my mother. I think the last two years of EMDR therapy have given me more insight and growth than 15 years of therapy.”

EMDR therapy can seem a little hokey if you’ve been taught to believe that therapy appointments involve lying on a couch and talking about your feelings. Due to limited evidence about its efficacy—at least when compared to established therapies like cognitive behavioral therapy—the APA only conditionally recommends the use of EMDR therapy in treating PTSD, meaning that they suggest it may be helpful to treat the condition. (Its panel of experts has suggested that they may amend their recommendation in future based on more recent evidence.)

Levis disputes the view that EMDR therapy is somehow less legitimate than other therapies. “There’s no voodoo here,” she says. “No hypnosis. But my clients do see something change.”

EMDR therapy is much less well-known than traditional talking therapies, in part because only three schools in the US offer masters programs in somatic psychology (EMDR therapy is a somatic approach, meaning it focuses on the connection between the body and mind.) Yokoyama adds that budding psychotherapists may swerve somatic therapies in favor of more evidence-based approaches—individuals can claim for EMDR therapy on health insurance plans, but other somatic approaches aren't always covered.

“Somatic theory is not very well known,” explains Yokoyama. “Our society is still a victim of Descartes’ theory of, 'I think, therefore I am’ and that priority is given to thoughts and top-down interventions, such as talking therapy. It takes a paradigm shift to seek out somatic psychotherapy approaches and to believe in the wisdom and the healing power of the body that extends past traditional physical treatment of symptoms, such as medication and surgery.”

For now, EMDR therapy is becoming seen as an increasingly legitimate treatment for PTSD. In 2005, the British authorities recommended EMDR therapy as a treatment for PTSD under the National Health Service (NHS). Advocates like Yokoyama argue that EMDR therapy can do more than just help those suffering from PTSD—it may provide relief for those suffering from a wider range of disorders, such as depression, obsessive compulsive disorder, psychosis, or even chronic pain conditions.

Survivors like Gonzalez and Fleming say EMDR therapy has done more than help them reprocess trauma—it’s made life worth living again. “I feel well rounded, I feel more balanced, I feel like I can handle situations without going into full on panic or crisis mode. I’m able to live my life. I’m no longer a victim,” Gonzalez says.

Fleming agrees. “EMDR therapy has given me hope. I never would have guessed that this freedom from my past would be possible. I still have trauma to reprocess, but I’m happy to be on the road of healing.”